Dental means and method



y 7 1949- E. E. BEERS 2,470,679

DENTAL MEANS AND METHOD Filed Oct. 19, 1945 EDWARD EBEERS INVENTOR:

' i hf AT TORN E 1 Patented May 17, 1949 UNITED STATES PATENT OFFICE DENTAL MEANS AND METHOD Edward E. Beers, Brooklyn, N. Y.

Application October 19, 1945, Serial No. 623,205

Claims.

This invention relates to dental means and methods for making and fitting dental plates to the upper gums of patients, especially at the forward portions to allow for good occlusion and capacity for biting with the front teeth.

The main object of the invention is to provide for a perfect fit of dental plates to the upper gums and roofs in the mouths of patients who must depend on such plates to provide all the upper teeth or the majority thereof.

Another object is to have means for taking impressions from a patients mouth in order to make a well fitting dental plate.

A further object is to specifically arrange for certain portions of the impression thus taken and thereafter the plate made therefrom to project in predetermined manner in order to allow for intermediate clearance and thereby ensure a complete fit of the resulting plate to the gums and roof of the patients mouth.

Other objects and the advantages inherent in and accruing from the practical application of my invention to the art will be set forth in detail as this specification proceeds, due reference being had to the accompanying drawing forming part hereof, and in which Fig. 1 is a perspective view of an impression tray adapted for use in the preliminary stage of the method of the invention,

Fig. 2 is a vertical section of the tray with plastic impression material applied thereto and inserted into a patients mouth and showing the gum cf the latter, being taken approximately on line 2-2 in Fig.1, and

Fig. 3 is a perspective view of a dental plate made according to certain features of the invention and embodying the same in a practical form and resulting from the previous steps involving the use of the means shown in Figs. 1 and 2, or of similar nature.

In the dental field, it is well known that it is always :a nice problem to make dental plates which will not only be plausibly comfortable to the patient wearing them, but will also be a good fit on his gums so that he .can chew with reasonable ease. without the plate involved being in danger of dropping out of the mouth. Especially is it important that the plate is such a good fit at the front that it will be possible to bite ofi morsels of food, etc, with the front teeth,

and likewise that rocking of the plate he definitely prevented. To arrive at such a perfect result is .far from the usual experience, being made particularly difficult by the nature and form of the :gums, portions of the latter hard and others soft and to some extent yieldmg. The latter characteristic makes impressions inaccurate and deceptive, so that the dental plates resulting from such impressions rock on inter mediate portions of the roof or gums in the mouth during mastication. and the front portion is spaced a slight distance from the lower edges of the upper gum so that the front teeth of the plate do not actually meet the teeth of the law or plate below. Such situation is very common and annoying, and in fact causes many peopl to remove their plates during meals, or at the very time when they should serve for mastication.

After studying the matter thoroughly with considerable experiment, I have found that it is possible to avoid deceptive impressions and poor fitting of plates to the upper gums and roofs of all patients requiring such plates by using certain means and following certain lines of procedure. and thereby ensure a positive and perfect fit of the dental plate to the upper gums and roof of the mouth.

Hence, in the practice of my invention, I prefer to employ an impression tray such as shown at In in the drawing, the same being provided with the usual handle H, scoop portion 12 with bounding wall 13 and bottom M. The bottom is either formed to have a front upward projection l5 and extreme side projections l6, l6 providing for side clearances ll, 11 between the central front projection and said extreme side projections, or the tray may be provided with a U-shaped insert l8 having the projections just mentioned. The main feature is, of course the central projection t5, for when the tray is used to take an impression as shown in Fig, 2, the front portion IQ of the upper gum is intended to rest on said portion 15, while at the rear, the gum 20 may be brought down toward or actually to the raised side projections It, the purpose of these side projections being merely to provide the clearance portions H to accommodate downward projections or irregularities 2i and ensure that the latter will not make any contact with the tray or its bottom 14.

For the purpose of taking an impression, the tray of course provided with .a plastic mass .22 in conventional manner, which will receive the intended impression of the upper gum 20, 2| and [9, the latter being the onl -y portion of the gum coming into deliberate contact at the front with central projection 15. Even if this actually causes a very slight compression of front portion 119 of the gum, this not do any harm, .as this portion must afterward be certain to make contact with the plate to be made so that the bite will be positive at the front, as will be explained.

When the plastic material 22 has set and been removed from the patients mouth, the usual procedure for making a denture or plate generally indicated in Fig. 3 at 23 is followed, it being clear that because of the upward projection or resting point l for the forward portion of the gum, a corresponding more or less raised portion 24 will be produced in the denture so as to ensure the positive contact of the front of the gum I9 with said portion 24, with the result that the front teeth 25 will make an effective biting contact with the teeth of the lower jaw or denture (not shown). As a rule, the projection 24 will not be as marked as shown in Fig. 3, the same being somewhat exaggerated to make it clearly evident. The depressed portions 26, 26 of the denture resulting at the sides from such front projection virtually form clearances for the side projections 2| of the upper gum 20 so that the denture 23 will not make contact with or rock on such projections on the gum. Instead, the rear portion 21 of the arcuate roof portion 28 of said denture will fit the roof of the patients mouth, as well as the rear portions 29, 29 the rear portions of the upper gum, the latter with forward portion 24 virtually forming a three point determining contact group for locating the denture on the upper gum. Of course, the sides 30, an, inner surface 3| of the front rim 32 and even the depressed portion 26, 26 of gum groove 33 serve simultaneously for accommodating the entire gum together with the roof portion 21 to form a comfortable fit of the denture in the patients mouth with certain assurance that no rocking of the denture will occur but instead a proper bite at the front will be obtained. The latter desirable result is mainly attained by the slight compression of the front portion [9 of the gum which is produced by projection l5 at the time the impression is made, in cooperation with the side clearances I1, I! in the tray which allow for the depressed portions 26, 26 in the denture. The rear portions or projections l6, 16 in the tray are not necessarily contact points, although they may be, but serve rather to level the tray with respect to the upper gum by preventing an oblique impression from resulting.

In a finished denture which is all too frequently found to be a poor fit when made by conventional methods, it is possible in at least some cases to bring it up to standard according to certain principles of this invention. This may be done by scraping out some of the mateiral of which it consists from the gum groove at the two sides 26, 26 as shown in the denture 23 of Fig. 3 and testing the fit until the depressed portions thus scraped tend to make only a comfortable or even no contact with the side portions of the gums. The result thus to be attained is to produce at least the previously mentioned three point contact at the front 24 and the rear 29, 29, also at 2? and portions 3G, 36. If this work is carefully done, the denture will fit so well that all mastication at meals may be readily performed in a manner which patients with dentures ordinarily fear to attempt.

Manifestly, the materials used may be any now known in the art or any which may be adopted as suitable, the invention referring to the methods of producing the above described denture and the denture resulting from the methods outlined.

Having now fully described my invention, I claim:

1. The method of making an impression form or cast in plastic material by using a tray, preparatory to making a denture, which consists in contacting the front central portion of the upper gum in the tray and simultaneously contacting the rear portions of both sides of the gum in said tray and at the same time avoiding contact in said tray with the intermediate portions of the sides of said gum, and thereby relieving the gum groove within the margin of the impression form or cast between the front central portion and the two rear side extremities thereof while producing said impression form or cast in plastic condition thereof.

2. The method of making an impression form or cast in plastic material by using a tray, preparatory to making a denture, which consists in contacting the front central portion of the upper gum in the tray to the exclusion of the sides intermediate said front central portion and the rear side portions of the gum and simultaneously broadly contacting the rear portion of the gum from one side thereof to the other in said tray and at the same time avoiding contact in said tray with the intermediate portions of the sides of said gum, and thereby relieving the gum groove within the margin of the impression form or cast between said central front portion and a broad transverse rear portion thereof while producing said impression form or cast in plastic condition thereof.

3. An impression tray for making an impression mold or cast based on three fixed points with reference to the upper gum of a patient, including the combination of a scoop proper having an arcuate bounding wall of U-shape with the ends thereof spaced apart and directed rearwardly to form a large opening therebetween, a handle for the scoop, a front central raised portion disposed within the arcuate portion of the bounding wall on the scoop forming a fixed projection for supportin the front central portion of the gum, and two raised portions forming a pair of fixed projections spaced apart and individually disposed within the side portions of the bounding wall at the rear portions of the sides of the scoop at the large opening thereon to support the two rear side portions of the gum to the exclusion of the intermediate portions of the sides of the latter.

4. An impression tray for making an impression mold or cast based on at least two fixed features with respect to the upper gum of a patient, including the combination of a scoop proper having an arcuate bounding edge and a large rear opening, a handle for the scoop, a front central raised portion disposed within the bounding edge of the scoop forming a fixed projection for supporting the front central portion of the gum, and raised fixed means disposed at the rear of said scoop within the large rear opening thereon effective to form a broad transversely arranged support for the rear portion of the impression mold or cast extending to both sides of said rear portion and exclusive of the intermediate portions of the sides of said impression mold or cast.

5. An impression tray for making an impression mold or cast based on three fixed points with reference to the upper gum of a patient, including the combination of a scoop proper having an arcuate bounding edge and a large rear opening, a handle for the scoop, a fixed ridge or interior marginal portion located within the outer arcuate bounding edge of the scoop, a front central raised integral portion upon the fixed ridge forming a high projection therein, and two rear raised integral portions forming high projections individually disposed upon the rear extremities of said fixed ridge at the large rear opening upon said scoop.

EDWARD E. BEERS.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number UNITED STATES PATENTS Name Date Foster Mar. 27, 1928 Heath June 26, 1928 FOREIGN PATENTS Country Date Great Britain June 30, 1939 

